Picture This: Galileo’s Birthday
Galileo Galilei, the famous astronomer, mathematician and physicist, was born on 15 February 1564.
He was the first person to develop and use a telescope to observe the night sky, but is remembered also for the persecution he endured for declaring that the sun, and not the earth, was at the centre of our solar system.
The theory had been developed by Copernicus, a Polish astronomer, who realized how controversial this discovery would be, and remained discreet about his findings.
However, Galileo, amongst others, publicly insisted that the theory was correct, and added further controversial suggestions about the scale of the universe. He was charged with heresy and was imprisoned and kept under house arrest for the rest of his life.
Credit: Corbis Images
Teaching Activity (age 9-14)
A pendulum is a mass which swings to and fro on a rope or string. Explain that Galileo investigated the factors that affect how a pendulum swings.
Set up a simple pendulum with a mass (e.g. a metal nut) suspended on a string. You will also need a timer.
Challenge the class to find out how the period of swing (i.e. the length of time from one extreme of the swing to the other) is affected by changing the following variables:
- mass on the end of the string
- the angle of the string at the start
- the length of the string
Learner Outcomes
Conducting an experiment, making and interpreting observations
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Thanks for the great Galileo write up and beautiful illustration.
Happy Birthday Galileo! Cheers to you! –Audrey Fischer